top of page

Lesson 8 - Lights, Buoys & Beacons

Introduction

  • Lights, buoys, and beacons are essential tools for safe navigation.

  • They guide mariners through channels, around hazards, and into harbors.

  • Understanding these aids is key to confident sailing.

​

Key factors affecting visibility:

  1. Brightness of the light (measured in candelas).

  2. Height of the light and observer’s eye.

  3. Weather conditions (fog, rain, or refraction).

Example: Pharos of Alexandria, visible up to 35 miles.

​

Light Characteristics

  • Fixed Lights: Steady and constant.

  • Flashing Lights: Dark intervals are longer than flashes.

  • Occulting Lights: Light is visible longer than darkness.

  • Morse Code Lights: Used for special warnings (e.g., “Mo(U)” for exclusion zones).

 

Sector & Directional Lights

  • Sector Lights: Different colors indicate safe passage or hazards.

    • Example: White = safe, Red = danger.

  • Directional Lights: Focused beams guide vessels along precise paths.​

​

Light Range and Visibility

  • Geographical Range: Distance over the horizon depends on height.

  • Meteorological Factors:

    • Fog and rain reduce visibility.

    • Atmospheric refraction can extend the visible range by up to 10%.

​

Buoyage Systems

​

IALA A:

  •  Red = Port

  •  Green = Starboard

 

IALA B:

  • Red = Starboard

  • Green = Port

​

Cardinal Marks

Cardinal marks indicate safe water relative to hazards.

  • North: Cones point up, continuous flashes.

  • East: Three flashes = "Three o’clock."

  • South: Six flashes + long flash = "Six o’clock."

  • West: Nine flashes, resembling a “waist.”

Mnemonic: Use the cone shapes to remember directions.​

Screenshot 2025-02-07 at 00.10.21.png
Screenshot 2025-02-07 at 00.11.23.png
Screenshot 2025-02-07 at 00.14.18.png

​Preferred Channel Marks

Indicate the main channel at junctions:

  • Red with green band: Preferred channel is to starboard.

  • Green with red band: Preferred channel is to port.​

Screenshot 2025-02-07 at 00.17.20.png

​Miscellaneous Marks

  • Safe Water Marks: Red and white stripes, signal clear water ahead.

  • Isolated Danger Marks: Black and red, mark hazards.

  • Special Marks: Yellow, indicate pipelines, racecourses, or military zones.

​

Screenshot 2025-02-07 at 00.19.25.png

Fog Signals

Used during low visibility (fog or mist). Types of fog signals:

  • Horns.

  • Bells.

  • Whistles.

Ensure safety when lights are not visible

​

Summary & Tips

  • Lighthouses use light patterns to communicate.

  • Buoys follow IALA A or B systems—know your region.

  • Cardinal and sector lights help navigate hazards and channels.

  • Fog signals provide safety in poor visibility.

  • Mastering these tools ensures confident and safe sailing.

​

​

Screenshot 2025-02-07 at 00.21.49.png
bottom of page